UV emitters have been used for decades for the disinfection of drinking water and waste water, in air conditioning system sumps and for the disinfection of work areas in biological laboratories.
In UV water treatment systems, UV-C irradiation sources are arranged in a quartz glass sheathing tube for irradiating the water. The cladding tube protects the irradiation source from external damage and at the same time ensures an efficient operating temperature.
UV disinfection systems comprise a number of UV emitters, arranged in at least one flow reactor through which the water passes. As it passes through the reactor, the water is subjected to a sufficient dose of UV-C irradiation to achieve the desired effect. A problem here is that the UV emitters are subject to natural ageing. Such ageing, which is associated with a drop in irradiated power, must therefore be monitored so that reliable UV-irradiation of the water is possible. If the irradiated power falls below a minimum, then the emitter must be replaced. The irradiated power given off is monitored by UV sensors.
These UV sensors are conventionally arranged in the flow reactor between the cladding tubes of the emitters and orthogonally to the emitter axes arranged in parallel to one another, so that the measured signal is essentially created through the overlaying of the radiation components from a number of irradiation sources. To allow continuous monitoring of the UV irradiation power across the flow reactor and to improve the operational safety of multi-beam systems, individual emitter monitoring is desirable.
From DE 297 07 052 U1 individual emitter monitoring is known, in which a UV sensor is arranged between the irradiation source and the cladding tube at a small distance from the irradiation source.